Will trees get enough nitrogen to sustain productivity in elevated CO2?

该项目建议通过研究土壤氮对植物的可用性和桉树林地树木对氮的利用，探索组织氮在未来二氧化碳（eCO2）升高时如何下降。植物冠层氮浓度下降，几乎每一个大规模的eCO2研究在本地土壤。该项目计划探索生态系统氮平衡的变化是如何发生的，方法是调查在eCO2下，由于植物活动与土壤氮可用性变化的平衡，叶氮是否下降。这些结果对于了解额外的氮在多大程度上“喂养”eCO2施肥反应并维持生产力的长期增长至关重要。预期成果可支持制定管理备选办法，以维持未来的森林生产力。

The project proposes to explore how tissue nitrogen declines in future elevated carbon dioxide (eCO2) by studying the availability of soil nitrogen to plants and use of nitrogen by Eucalyptus woodland trees. Plant canopy nitrogen concentrations decline in nearly every large-scale eCO2 study done on native soils. The project plans to explore how changes in ecosystem nitrogen balance occur, by investigating if leaf nitrogen declines under eCO2 due to the balance of plant activity versus changes in soil nitrogen availability. The outcomes are central to knowing the extent to which extra nitrogen ‘feeds’ the eCO2 fertilisation response and sustains long-term increases in productivity. Expected outcomes may support the development of management options to sustain future forest productivity.